dump rsyslog messages to psql if set

This allows users the capability to set some config vars in etcd to dump logs over to a postgresql database for processing. Usage:

```
$ etcdctl set /deis/logger/dbHost 192.168.0.1
$ etcdctl set /deis/logger/dbUser deis
$ etcdctl set /deis/logger/dbPassword supersecretpassword
$ etcdctl set /deis/logger/dbName rsyslog
```